Envelope blank



ENVELOPE .amnx

Filed Feb; 1, 1954 2 Sheets-Sheet 2 JiTazsrzf n Win/a 1 ,s'wf

Patented July 20, 19.37

Willard E. Swift, Worcester,

United States Envelope Company, Mass, a corporation of Maine Mass, assignor to Springfield,

Application February 1, 1934, Serial No. 109,356

3 Claims. (Cl. 229-75) The present invention relates to envelopes," and has for its object to provide an improved form of envelope blank prepared in such a manner that envelope blanks embodying the invention may be 5 marketed in a flat condition for conversion into completed envelopes by the users, as desired.

According to the present invention, certain predetermined areas of each envelope blank are coated with an adhesive of such'character that the coated areas adhere strongly to each other when pressed into contact, without requiring any moistening, although such coated areas will not adhere to uncoated areas of the blank. Therefore, each prepared blank may be quickly con- 15. verted' into an envelope by merely applying pressure to overlying dry-sealing adhesive areas, and then after being loaded, the envelope can be sealed by pressure, alone, exerted along the edge of the folded over seal flap. Envelope blanks 20 prepared in accordance with the invention may be packed and stored much more economically than is possible with completed envelopes, which usually require packaging, and the above and other advantageous features of the invention will hereinafter more fully appear'from the following description with reference to the accompanying drawings; in which:-.

Fig. 1 is a diagrammaticview illustrating the manufacture of envelope "blanks in accordance with one form of the invention.

Fig. 2 shows a prepared blank initially folded for conversion into an envelope.

Fig. 3 shows the blank of Fig. 2 completely folded and sealed, as an envelope.

3 Fig. 4 is a diagrammatic view similar to Fig. 1,

showing the manufacture ofa modified form of envelope blank. F1Fig. 5 shows the reverse side of the blank of 4. r Fig. 6 illustrates initial folding of the blank of Fig. 5, preparatory to forming an envelope. Fig. 7 shows the blank of Fig. 6 completely folded and sealed, as an envelope. Like reference characters refer to like parts in the different figures. J

Referring first to Fig. 1, a web I, of envelope material is fed by any suitable means, and as it travels has applied thereto adhesively coated areas 2 and 3 on one side and other adhesively coated areas 4 and on the opposite side. The areas 3 and 5, extending longitudinally on opposite sides of the webl are parallel, although at different distances from the central axis of the wee, while the areas 2 and 4 extending trans- 55 versely of the web are of substantially the same form, with the area 4 joining the spaced areas 5 The adhesive of the areas 2, 3, 4, and 5 is of such a character that one gummed area will adhere to any other gummed area when pressed into non-moistened contact, while no one gummed area will adhere of itself to the material of which the web is made. Preferably the gumming is applied in-the form of a'dispersedrubber solution,

or natural or compounded latex, the invention also contemplating the use of other similar drysealing adhesives in the form of thermo-plastics such as arclor re'sins or galyptols, either alone or in combination with rubber.

After application of the gumming 2, 3, 4, and 5 to the web as shown, the advancing end of the web is out and scored to provide a complete envelope blank, as shown at the left in Fig. 1, In the complete blank, the gumming 2 is disposed along one edge of the seal flap 6, while the gum-v ming 4 and 5 is disposed around the edges of the back flap 1, although on the opposite side. The gumming 3 is disposed on wings or side flaps 8 projecting oppositely from the body of the blank, with score lines 9, l0, and H defining the junctions of the seal flap 6, back flap I and side flaps 8 respectively, with the body of the blank, as indicated in dot and dash lines.

When it is desired to convert the blank into an envelope, the back flap I is folded along the score line III, as shown in Fig. 2, which disposes the gummed areas 5 between the gummed areas 3 on the side flaps 8.. The side flaps 8 are then folded along the score lines II to bring the respective pairs of gummed areas 3 and 5 into overlying relation, so that the envelope is completed by the,

application'of pressure to the overlying gummed areas. After an enclosure has been placed in a completed envelope, it may be sealed by folding down the seal flap 6 alongthe score line 9 to bring the gummed area 2 into overlying relation with the gummed area 4, the engagement of these areas, accompanled by pressure, serving to effectively seal the envelope.

Referring now to Fig. 4, there is shown the manufacture of blanks for a different type of envelope, in which a traveling web l2 has applied thereto oppositely disposed areas I3 and I4 coated with a dry-sealing adhesive of the same character described with reference to Fig. 1. A blank is then cut from the advancing endof the web. l2 after the gumming, which blank consists. of a seal flap'l5, bottom flap l6 and side flaps I'I. After the blank has been cut, the side flaps l'l thereof are correspondingly gummed as indicated at IS in Fig. 5, this gumming being applied to the opposite side of the blank from the previously applied gumming l3 and I4. At the same time, the bottom flap I B'has a small gummed area l9 applied to the apex of the flap, the purpose of which will shortly appear. Score lines 20, 2|, and 22 are also provided between the seal flap i5, bottom flap l6 and side flaps l1 respectively, as indicated by the dot and dash lines.

When it is desired to convert the blank of Fig. 5 into an envelope, the side flaps I1 are folded along the score lines 22 to bring the side flaps into the position shown in Fig. 6, wherein the U-shaped gummed areas l8 extend in opposite directions. Therefore, when the bottom flap I6 is folded over along score line 2|, its gummed area I! coincides with the lower portion of the combined gummed areas I8 on the folded over side flaps I1. The application of pressure to the overlying gummed areas completes the envelope, and after the placing of an enclosure in the envelope it may be effectively sealed by folding over the seal flap ii to bring its gummed area l3 into engagement with the upper portion of the combined gummed areas It. In the folded over position of the seal flap l5, its apex registers with the gummed portion I 9 at the apex of the bottom flap l6, thereby insuring that the tip of the seal flap will be firmly secured.

From the foregoing, it is apparent that by the present invention there is provided an improved form of envelope and a blank therefor such that prepared blanks can be readily converted into envelopes by merely applying pressure to. overlying dry-sealing areas of a folded blank. The adhesion between these gummed 'areas in a completed envelope is very great, so

that the envelope remains effectively sealed, and due to the waterproof quality of the gumming, an envelope cannot be surreptitiously opened, as by steaming. Envelope blanks prepared in accordance with the invention can be packed in fiat form for marketing, without any possibility of the gummed areas on one side of a blank coming into contact with the gummed areas on the opposite side of the next blank in the stack, it

being evident from Figs. 1 and 5 that the gummed areas of contacting blank faces are never in' register.

I claim,

1. As a new article of manufacture, an envelope blank adapted to be converted by the user thereof into a completed envelope, without resort to wet-gluing of its seams or of its sealing means, said blank having a rectangular body portion adapted to provide one wall of the envelope, and having two opposite side flaps and a back flap adapted to cooperate in forming the other envelope wall, the said side flaps on one side of the blank having areas coated with dry-sealing adhesive, and the said back flap on the opposite side of the blank having areas coated with drysealing adhesive, and adapted to register with and adhere to said side flap areas upon the folding over and down of said back and side flaps, to form the envelopes last-mentioned wall, said blank providing also a closure flap having on one side of the blank an area coated with dry-sealing adhesive, for registration, upon the folding down of said closure flap, with a corresponding drysealing adhesive area on said last-mentioned wall of the envelope.

2. As a. new article of manufacture, an envelope blank adapted to be converted by the user thereof into a completed envelope, without resort to wet-gluing of its seams or of its sealing means, said blank having a rectangular body portion adapted to provide one wall of the envelope, and having two opposite side flaps and a back flap adapted to cooperate in forming the other envelope wall, the said side flaps onone side of the blank having areas coated with dry-sealing adhesive, and the said back flap on the ,opposite side of the blank having areas coated with drysealing adhesive, and adapted to register with and adhere to said side flap areas upon the initial folding over and down-of said back flap, followed by folding over and down of said side flaps, said back flap, on the same side'of the blank as its said dry-adhesive coated areas, having another area coated with dry-sealing adhesive, and a closure flap having, on the same side of the blank as the side flap areas of dry-sealing adhesive, an area floated with dry-sealing adhesive and adapted to register with and adhere to said last-mentioned back flap dry-sealingadhesive area when said closure flap is folded down to close the envelope.

'3. As a new article of manufacture, an envelope blank adapted to be converted by the user thereof into a completed envelope, without resort to wet-gluing of its seams or of its sealing means, said blank having a rectangular body portion adapted to provide one wall of the envelope, and having two opposite side flaps and a back flap adapted to cooperate in forming the other envelope wall, the said side flaps on one side of the blank having areas coated with drysealing adhesive, and the said back flap on the opposite side of the blank having areas coated with dry-sealing adhesive, and adapted to register with and adhere to said side flap areas upon the initial folding over and down of said side flaps, followed by folding over and down of said back flap, said side flaps, on the same side of the blank as their said dry-sealing adhesive coated areas, having other areas coated with dry-sealing adhesive, and a closure flap having, on the same side of the blank as the back flap areas of drysealing adhesive, an area coated with dry-sealing adhesive and adapted to register with and adhere to said last-mentioned other side flap drysealing adhesive areas, when said closure flap is folded down to close the envelope.

. WILLARD E. SWIFT. 

